METHOD OF PRODUCING P-AMINOPHENOL AND DEVICE FOR PRODUCING P-AMINOPHENOL USING THIS METHOD Russian patent published in 2024 - IPC C07C201/00 C07C213/02 

FIELD: chemical or physical processes.

SUBSTANCE: invention relates to a method of producing p-aminophenol. Method involves two steps—1) obtaining p-nitrosophenol and 2) obtaining p-aminophenol. At step 1), a solution of p-nitrosophenol in acetic acid is obtained, wherein step 1) includes steps i)–vi). At step i), water, an aqueous solution of sodium nitrite and an aqueous solution of phenol are fed into the reactor to obtain a reaction mixture, note here that preset pH value of reaction mixture is maintained, not exceeding 3, temperature in reactor maintained at 2–7 °C and gas current is fed into reactor to create inert atmosphere. At step ii), the reaction mixture is stirred to obtain a precipitate-containing solution. At step iii), the precipitate-containing solution is fed to a filter for separation into a precipitate and a solution. At step iv), the precipitate is washed in the filter with water and the precipitate is dried. At step v), the precipitate is washed in the filter with acetic acid. At step vi), acetic acid used at step v), which is a solution of p-nitrosophenol in acetic acid, is carried off to the next step. At step 2) p-aminophenol is obtained, wherein step 2) includes steps a)–e). At step a), a solution of p-nitrosophenol in acetic acid and zinc powder are fed into the reactor, and they are mixed to obtain a reaction mixture, note here that gas current is fed into reactor to create inert atmosphere. At step b), the reaction mixture is stirred in a reactor and held at a temperature not higher than 55 °C to obtain a precipitate-containing solution. At step c), the solution containing the precipitate is held in a reactor at temperature of 2–10 °C for at least 10 minutes. At step d), the precipitate-containing solution is fed to a filter for separation into a precipitate and a solution. At step e), the solution obtained at step d) is carried off for further treatment. Invention also relates to a device for producing p-aminophenol using said method.

EFFECT: reducing the number of operations and time of the process, ensuring its continuity, as well as increasing the output of the product and reducing the amount of liquid wastes.

39 cl, 4 dwg, 1 ex